pdo_stmt.c

/*
  +----------------------------------------------------------------------+
  | Copyright (c) The PHP Group                                          |
  +----------------------------------------------------------------------+
  | This source file is subject to version 3.01 of the PHP license,      |
  | that is bundled with this package in the file LICENSE, and is        |
  | available through the world-wide-web at the following url:           |
  | https://www.php.net/license/3_01.txt                                 |
  | If you did not receive a copy of the PHP license and are unable to   |
  | obtain it through the world-wide-web, please send a note to          |
  | license@php.net so we can mail you a copy immediately.               |
  +----------------------------------------------------------------------+
  | Author: Wez Furlong <wez@php.net>                                    |
  |         Marcus Boerger <helly@php.net>                               |
  |         Sterling Hughes <sterling@php.net>                           |
  +----------------------------------------------------------------------+
*/

/* The PDO Statement Handle Class */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "php.h"
#include "php_ini.h"
#include "ext/standard/info.h"
#include "ext/standard/php_var.h"
#include "php_pdo.h"
#include "php_pdo_driver.h"
#include "php_pdo_int.h"
#include "zend_exceptions.h"
#include "zend_interfaces.h"
#include "php_memory_streams.h"
#include "pdo_stmt_arginfo.h"

#define PHP_STMT_GET_OBJ \
	pdo_stmt_t *stmt = Z_PDO_STMT_P(ZEND_THIS); \
	if (!stmt->dbh) { \
		zend_throw_error(NULL, "PDO object is uninitialized"); \
		RETURN_THROWS(); \
	} \

static inline bool rewrite_name_to_position(pdo_stmt_t *stmt, struct pdo_bound_param_data *param) /* {{{ */
{
	if (stmt->bound_param_map) {
		/* rewriting :name to ? style.
		 * We need to fixup the parameter numbers on the parameters.
		 * If we find that a given named parameter has been used twice,
		 * we will raise an error, as we can't be sure that it is safe
		 * to bind multiple parameters onto the same zval in the underlying
		 * driver */
		zend_string *name;
		int position = 0;

		if (stmt->named_rewrite_template) {
			/* this is not an error here */
			return 1;
		}
		if (!param->name) {
			/* do the reverse; map the parameter number to the name */
			if ((name = zend_hash_index_find_ptr(stmt->bound_param_map, param->paramno)) != NULL) {
				param->name = zend_string_copy(name);
				return 1;
			}
			/* TODO Error? */
			pdo_raise_impl_error(stmt->dbh, stmt, "HY093", "parameter was not defined");
			return 0;
		}

		ZEND_HASH_FOREACH_PTR(stmt->bound_param_map, name) {
			if (!zend_string_equals(name, param->name)) {
				position++;
				continue;
			}
			if (param->paramno >= 0) {
				/* TODO Error? */
				pdo_raise_impl_error(stmt->dbh, stmt, "IM001", "PDO refuses to handle repeating the same :named parameter for multiple positions with this driver, as it might be unsafe to do so.  Consider using a separate name for each parameter instead");
				return -1;
			}
			param->paramno = position;
			return 1;
		} ZEND_HASH_FOREACH_END();
		/* TODO Error? */
		pdo_raise_impl_error(stmt->dbh, stmt, "HY093", "parameter was not defined");
		return 0;
	}
	return 1;
}
/* }}} */

/* trigger callback hook for parameters */
static bool dispatch_param_event(pdo_stmt_t *stmt, enum pdo_param_event event_type) /* {{{ */
{
	bool ret = 1, is_param = 1;
	struct pdo_bound_param_data *param;
	HashTable *ht;

	if (stmt->dbh->skip_param_evt & (1 << event_type)) {
		return 1;
	}

	if (!stmt->methods->param_hook) {
		return 1;
	}

	ht = stmt->bound_params;

iterate:
	if (ht) {
		ZEND_HASH_FOREACH_PTR(ht, param) {
			if (!stmt->methods->param_hook(stmt, param, event_type)) {
				ret = 0;
				break;
			}
		} ZEND_HASH_FOREACH_END();
	}
	if (ret && is_param) {
		ht = stmt->bound_columns;
		is_param = 0;
		goto iterate;
	}

	return ret;
}
/* }}} */

bool pdo_stmt_describe_columns(pdo_stmt_t *stmt) /* {{{ */
{
	int col;

	stmt->columns = ecalloc(stmt->column_count, sizeof(struct pdo_column_data));

	for (col = 0; col < stmt->column_count; col++) {
		if (!stmt->methods->describer(stmt, col)) {
			return false;
		}

		/* if we are applying case conversions on column names, do so now */
		if (stmt->dbh->native_case != stmt->dbh->desired_case && stmt->dbh->desired_case != PDO_CASE_NATURAL) {
			zend_string *orig_name = stmt->columns[col].name;
			switch (stmt->dbh->desired_case) {
				case PDO_CASE_LOWER:
					stmt->columns[col].name = zend_string_tolower(orig_name);
					zend_string_release(orig_name);
					break;
				case PDO_CASE_UPPER: {
					stmt->columns[col].name = zend_string_separate(orig_name, 0);
					char *s = ZSTR_VAL(stmt->columns[col].name);
					while (*s != '\0') {
						*s = toupper(*s);
						s++;
					}
					break;
				}
				EMPTY_SWITCH_DEFAULT_CASE()
			}
		}

		/* update the column index on named bound parameters */
		if (stmt->bound_columns) {
			struct pdo_bound_param_data *param;

			if ((param = zend_hash_find_ptr(stmt->bound_columns,
					stmt->columns[col].name)) != NULL) {
				param->paramno = col;
			}
		}

	}
	return true;
}
/* }}} */

static void pdo_stmt_reset_columns(pdo_stmt_t *stmt) {
	if (stmt->columns) {
		int i;
		struct pdo_column_data *cols = stmt->columns;

		for (i = 0; i < stmt->column_count; i++) {
			if (cols[i].name) {
				zend_string_release_ex(cols[i].name, 0);
			}
		}
		efree(stmt->columns);
	}
	stmt->columns = NULL;
	stmt->column_count = 0;
}

/**
 * Change the column count on the statement. If it differs from the previous one,
 * discard existing columns information.
 */
PDO_API void php_pdo_stmt_set_column_count(pdo_stmt_t *stmt, int new_count)
{
	/* Columns not yet "described". */
	if (!stmt->columns) {
		stmt->column_count = new_count;
		return;
	}

	/* The column count has not changed: No need to reload columns description.
	 * Note: Do not handle attribute name change, without column count change. */
	if (new_count == stmt->column_count) {
		return;
	}

	/* Free previous columns to force reload description. */
	pdo_stmt_reset_columns(stmt);
	stmt->column_count = new_count;
}

static void get_lazy_object(pdo_stmt_t *stmt, zval *return_value) /* {{{ */
{
	if (Z_ISUNDEF(stmt->lazy_object_ref)) {
		pdo_row_t *row = ecalloc(1, sizeof(pdo_row_t));
		row->stmt = stmt;
		zend_object_std_init(&row->std, pdo_row_ce);
		ZVAL_OBJ(&stmt->lazy_object_ref, &row->std);
		GC_ADDREF(&stmt->std);
		GC_DELREF(&row->std);
	}
	ZVAL_COPY(return_value, &stmt->lazy_object_ref);
}
/* }}} */

static void param_dtor(zval *el) /* {{{ */
{
	struct pdo_bound_param_data *param = (struct pdo_bound_param_data *)Z_PTR_P(el);

	/* tell the driver that it is going away */
	if (param->stmt->methods->param_hook) {
		param->stmt->methods->param_hook(param->stmt, param, PDO_PARAM_EVT_FREE);
	}

	if (param->name) {
		zend_string_release_ex(param->name, 0);
	}

	if (!Z_ISUNDEF(param->parameter)) {
		zval_ptr_dtor(&param->parameter);
		ZVAL_UNDEF(&param->parameter);
	}
	if (!Z_ISUNDEF(param->driver_params)) {
		zval_ptr_dtor(&param->driver_params);
	}
	efree(param);
}
/* }}} */

static bool really_register_bound_param(struct pdo_bound_param_data *param, pdo_stmt_t *stmt, bool is_param) /* {{{ */
{
	HashTable *hash;
	zval *parameter;
	struct pdo_bound_param_data *pparam = NULL;

	hash = is_param ? stmt->bound_params : stmt->bound_columns;

	if (!hash) {
		ALLOC_HASHTABLE(hash);
		zend_hash_init(hash, 13, NULL, param_dtor, 0);

		if (is_param) {
			stmt->bound_params = hash;
		} else {
			stmt->bound_columns = hash;
		}
	}

	if (!Z_ISREF(param->parameter)) {
		parameter = &param->parameter;
	} else {
		parameter = Z_REFVAL(param->parameter);
	}

	if (PDO_PARAM_TYPE(param->param_type) == PDO_PARAM_STR && param->max_value_len <= 0 && !Z_ISNULL_P(parameter)) {
		if (!try_convert_to_string(parameter)) {
			return 0;
		}
	} else if (PDO_PARAM_TYPE(param->param_type) == PDO_PARAM_INT && (Z_TYPE_P(parameter) == IS_FALSE || Z_TYPE_P(parameter) == IS_TRUE)) {
		convert_to_long(parameter);
	} else if (PDO_PARAM_TYPE(param->param_type) == PDO_PARAM_BOOL && Z_TYPE_P(parameter) == IS_LONG) {
		convert_to_boolean(parameter);
	}

	param->stmt = stmt;
	param->is_param = is_param;

	if (Z_REFCOUNTED(param->driver_params)) {
		Z_ADDREF(param->driver_params);
	}

	if (!is_param && param->name && stmt->columns) {
		/* try to map the name to the column */
		int i;

		for (i = 0; i < stmt->column_count; i++) {
			if (zend_string_equals(stmt->columns[i].name, param->name)) {
				param->paramno = i;
				break;
			}
		}

		/* if you prepare and then execute passing an array of params keyed by names,
		 * then this will trigger, and we don't want that */
		if (param->paramno == -1) {
			/* Should this always be an Error? */
			char *tmp;
			/* TODO Error? */
			spprintf(&tmp, 0, "Did not find column name '%s' in the defined columns; it will not be bound", ZSTR_VAL(param->name));
			pdo_raise_impl_error(stmt->dbh, stmt, "HY000", tmp);
			efree(tmp);
		}
	}

	if (param->name) {
		if (is_param && ZSTR_VAL(param->name)[0] != ':') {
			zend_string *temp = zend_string_alloc(ZSTR_LEN(param->name) + 1, 0);
			ZSTR_VAL(temp)[0] = ':';
			memmove(ZSTR_VAL(temp) + 1, ZSTR_VAL(param->name), ZSTR_LEN(param->name) + 1);
			param->name = temp;
		} else {
			param->name = zend_string_init(ZSTR_VAL(param->name), ZSTR_LEN(param->name), 0);
		}
	}

	if (is_param && !rewrite_name_to_position(stmt, param)) {
		if (param->name) {
			zend_string_release_ex(param->name, 0);
			param->name = NULL;
		}
		return 0;
	}

	/* ask the driver to perform any normalization it needs on the
	 * parameter name.  Note that it is illegal for the driver to take
	 * a reference to param, as it resides in transient storage only
	 * at this time. */
	if (stmt->methods->param_hook) {
		if (!stmt->methods->param_hook(stmt, param, PDO_PARAM_EVT_NORMALIZE)) {
			PDO_HANDLE_STMT_ERR();
			if (param->name) {
				zend_string_release_ex(param->name, 0);
				param->name = NULL;
			}
			return 0;
		}
	}

	/* delete any other parameter registered with this number.
	 * If the parameter is named, it will be removed and correctly
	 * disposed of by the hash_update call that follows */
	if (param->paramno >= 0) {
		zend_hash_index_del(hash, param->paramno);
	}

	/* allocate storage for the parameter, keyed by its "canonical" name */
	if (param->name) {
		pparam = zend_hash_update_mem(hash, param->name, param, sizeof(struct pdo_bound_param_data));
	} else {
		pparam = zend_hash_index_update_mem(hash, param->paramno, param, sizeof(struct pdo_bound_param_data));
	}

	/* tell the driver we just created a parameter */
	if (stmt->methods->param_hook) {
		if (!stmt->methods->param_hook(stmt, pparam, PDO_PARAM_EVT_ALLOC)) {
			PDO_HANDLE_STMT_ERR();
			/* undo storage allocation; the hash will free the parameter
			 * name if required */
			if (pparam->name) {
				zend_hash_del(hash, pparam->name);
			} else {
				zend_hash_index_del(hash, pparam->paramno);
			}
			/* param->parameter is freed by hash dtor */
			ZVAL_UNDEF(&param->parameter);
			return 0;
		}
	}
	return 1;
}
/* }}} */

/* {{{ Execute a prepared statement, optionally binding parameters */
PHP_METHOD(PDOStatement, execute)
{
	zval *input_params = NULL;
	int ret = 1;

	ZEND_PARSE_PARAMETERS_START(0, 1)
		Z_PARAM_OPTIONAL
		Z_PARAM_ARRAY_OR_NULL(input_params)
	ZEND_PARSE_PARAMETERS_END();

	PHP_STMT_GET_OBJ;
	PDO_STMT_CLEAR_ERR();

	if (input_params) {
		struct pdo_bound_param_data param;
		zval *tmp;
		zend_string *key = NULL;
		zend_ulong num_index;

		if (stmt->bound_params) {
			zend_hash_destroy(stmt->bound_params);
			FREE_HASHTABLE(stmt->bound_params);
			stmt->bound_params = NULL;
		}

		ZEND_HASH_FOREACH_KEY_VAL(Z_ARRVAL_P(input_params), num_index, key, tmp) {
			memset(&param, 0, sizeof(param));

			if (key) {
				/* yes this is correct.  we don't want to count the null byte.  ask wez */
				param.name = key;
				param.paramno = -1;
			} else {
				/* we're okay to be zero based here */
				/* num_index is unsignend */
				param.paramno = num_index;
			}

			param.param_type = PDO_PARAM_STR;
			ZVAL_COPY(&param.parameter, tmp);

			if (!really_register_bound_param(&param, stmt, 1)) {
				if (!Z_ISUNDEF(param.parameter)) {
					zval_ptr_dtor(&param.parameter);
				}
				RETURN_FALSE;
			}
		} ZEND_HASH_FOREACH_END();
	}

	if (PDO_PLACEHOLDER_NONE == stmt->supports_placeholders) {
		/* handle the emulated parameter binding,
		 * stmt->active_query_string holds the query with binds expanded and
		 * quoted.
		 */

		/* string is leftover from previous calls so PDOStatement::debugDumpParams() can access */
		if (stmt->active_query_string) {
			zend_string_release(stmt->active_query_string);
			stmt->active_query_string = NULL;
		}

		ret = pdo_parse_params(stmt, stmt->query_string, &stmt->active_query_string);

		if (ret == 0) {
			/* no changes were made */
			stmt->active_query_string = zend_string_copy(stmt->query_string);
			ret = 1;
		} else if (ret == -1) {
			/* something broke */
			RETURN_FALSE;
		}
	} else if (!dispatch_param_event(stmt, PDO_PARAM_EVT_EXEC_PRE)) {
		PDO_HANDLE_STMT_ERR();
		RETURN_FALSE;
	}
	if (stmt->methods->executer(stmt)) {
		if (!stmt->executed) {
			/* this is the first execute */

			if (stmt->dbh->alloc_own_columns && !stmt->columns) {
				/* for "big boy" drivers, we need to allocate memory to fetch
				 * the results into, so lets do that now */
				ret = pdo_stmt_describe_columns(stmt);
			}

			stmt->executed = 1;
		}

		if (ret && !dispatch_param_event(stmt, PDO_PARAM_EVT_EXEC_POST)) {
			PDO_HANDLE_STMT_ERR();
			RETURN_FALSE;
		}

		RETURN_BOOL(ret);
	}
	PDO_HANDLE_STMT_ERR();
	RETURN_FALSE;
}
/* }}} */

static inline void fetch_value(pdo_stmt_t *stmt, zval *dest, int colno, enum pdo_param_type *type_override) /* {{{ */
{
	if (colno < 0) {
		zend_value_error("Column index must be greater than or equal to 0");
		ZVAL_NULL(dest);
		return;
	}

	if (colno >= stmt->column_count) {
		zend_value_error("Invalid column index");
		ZVAL_NULL(dest);
		return;
	}

	ZVAL_NULL(dest);
	stmt->methods->get_col(stmt, colno, dest, type_override);

	if (Z_TYPE_P(dest) == IS_STRING && Z_STRLEN_P(dest) == 0
			&& stmt->dbh->oracle_nulls == PDO_NULL_EMPTY_STRING) {
		zval_ptr_dtor_str(dest);
		ZVAL_NULL(dest);
	}

	/* If stringification is requested, override with PDO_PARAM_STR. */
	enum pdo_param_type pdo_param_str = PDO_PARAM_STR;
	if (stmt->dbh->stringify) {
		type_override = &pdo_param_str;
	}

	if (type_override && Z_TYPE_P(dest) != IS_NULL) {
		switch (*type_override) {
			case PDO_PARAM_INT:
				convert_to_long(dest);
				break;
			case PDO_PARAM_BOOL:
				convert_to_boolean(dest);
				break;
			case PDO_PARAM_STR:
				if (Z_TYPE_P(dest) == IS_FALSE) {
					/* Return "0" rather than "", because this is what database drivers that
					 * don't have a dedicated boolean type would return. */
					zval_ptr_dtor_nogc(dest);
					ZVAL_INTERNED_STR(dest, ZSTR_CHAR('0'));
				} else if (Z_TYPE_P(dest) == IS_RESOURCE) {
					/* Convert LOB stream to string */
					php_stream *stream;
					php_stream_from_zval_no_verify(stream, dest);
					zend_string *str = php_stream_copy_to_mem(stream, PHP_STREAM_COPY_ALL, 0);
					zval_ptr_dtor_nogc(dest);
					if (str == NULL) {
						ZVAL_EMPTY_STRING(dest);
					} else {
						ZVAL_STR(dest, str);
					}
				} else {
					convert_to_string(dest);
				}
				break;
			case PDO_PARAM_NULL:
				convert_to_null(dest);
				break;
			case PDO_PARAM_LOB:
				if (Z_TYPE_P(dest) == IS_STRING) {
					php_stream *stream =
						php_stream_memory_open(TEMP_STREAM_READONLY, Z_STR_P(dest));
					zval_ptr_dtor_str(dest);
					php_stream_to_zval(stream, dest);
				}
				break;
			default:
				break;
		}
	}

	if (Z_TYPE_P(dest) == IS_NULL && stmt->dbh->oracle_nulls == PDO_NULL_TO_STRING) {
		ZVAL_EMPTY_STRING(dest);
	}
}
/* }}} */

static bool do_fetch_common(pdo_stmt_t *stmt, enum pdo_fetch_orientation ori, zend_long offset) /* {{{ */
{
	if (!stmt->executed) {
		return 0;
	}

	if (!dispatch_param_event(stmt, PDO_PARAM_EVT_FETCH_PRE)) {
		return 0;
	}

	if (!stmt->methods->fetcher(stmt, ori, offset)) {
		return 0;
	}

	/* some drivers might need to describe the columns now */
	if (!stmt->columns && !pdo_stmt_describe_columns(stmt)) {
		return 0;
	}

	if (!dispatch_param_event(stmt, PDO_PARAM_EVT_FETCH_POST)) {
		return 0;
	}

	if (stmt->bound_columns) {
		/* update those bound column variables now */
		struct pdo_bound_param_data *param;

		ZEND_HASH_FOREACH_PTR(stmt->bound_columns, param) {
			if (param->paramno >= 0) {
				if (!Z_ISREF(param->parameter)) {
					continue;
				}

				/* delete old value */
				zval_ptr_dtor(Z_REFVAL(param->parameter));

				/* set new value */
				fetch_value(stmt, Z_REFVAL(param->parameter), param->paramno, &param->param_type);

				/* TODO: some smart thing that avoids duplicating the value in the
				 * general loop below.  For now, if you're binding output columns,
				 * it's better to use LAZY or BOUND fetches if you want to shave
				 * off those cycles */
			}
		} ZEND_HASH_FOREACH_END();
	}

	return 1;
}
/* }}} */

static bool do_fetch_class_prepare(pdo_stmt_t *stmt) /* {{{ */
{
	zend_class_entry *ce = stmt->fetch.cls.ce;
	zend_fcall_info *fci = &stmt->fetch.cls.fci;
	zend_fcall_info_cache *fcc = &stmt->fetch.cls.fcc;

	fci->size = sizeof(zend_fcall_info);

	if (!ce) {
		stmt->fetch.cls.ce = ZEND_STANDARD_CLASS_DEF_PTR;
		ce = ZEND_STANDARD_CLASS_DEF_PTR;
	}

	if (ce->constructor) {
		ZVAL_UNDEF(&fci->function_name);
		fci->retval = &stmt->fetch.cls.retval;
		fci->param_count = 0;
		fci->params = NULL;

		zend_fcall_info_args_ex(fci, ce->constructor, &stmt->fetch.cls.ctor_args);

		fcc->function_handler = ce->constructor;
		fcc->called_scope = ce;
		return 1;
	} else if (!Z_ISUNDEF(stmt->fetch.cls.ctor_args)) {
		zend_throw_error(NULL, "User-supplied statement does not accept constructor arguments");
		return 0;
	} else {
		return 1; /* no ctor no args is also ok */
	}
}
/* }}} */

static bool make_callable_ex(pdo_stmt_t *stmt, zval *callable, zend_fcall_info * fci, zend_fcall_info_cache * fcc, int num_args) /* {{{ */
{
	char *is_callable_error = NULL;

	if (zend_fcall_info_init(callable, 0, fci, fcc, NULL, &is_callable_error) == FAILURE) {
		if (is_callable_error) {
			zend_type_error("%s", is_callable_error);
			efree(is_callable_error);
		} else {
			zend_type_error("User-supplied function must be a valid callback");
		}
		return false;
	}
	if (is_callable_error) {
		/* Possible error message */
		efree(is_callable_error);
	}

	fci->param_count = num_args; /* probably less */
	fci->params = safe_emalloc(sizeof(zval), num_args, 0);

	return true;
}
/* }}} */

static bool do_fetch_func_prepare(pdo_stmt_t *stmt) /* {{{ */
{
	zend_fcall_info *fci = &stmt->fetch.cls.fci;
	zend_fcall_info_cache *fcc = &stmt->fetch.cls.fcc;

	if (!make_callable_ex(stmt, &stmt->fetch.func.function, fci, fcc, stmt->column_count)) {
		return false;
	} else {
		stmt->fetch.func.values = safe_emalloc(sizeof(zval), stmt->column_count, 0);
		return true;
	}
}
/* }}} */

static void do_fetch_opt_finish(pdo_stmt_t *stmt, int free_ctor_agrs) /* {{{ */
{
	/* fci.size is used to check if it is valid */
	if (stmt->fetch.cls.fci.size && stmt->fetch.cls.fci.params) {
		if (!Z_ISUNDEF(stmt->fetch.cls.ctor_args)) {
			/* Added to free constructor arguments */
			zend_fcall_info_args_clear(&stmt->fetch.cls.fci, 1);
		} else {
			efree(stmt->fetch.cls.fci.params);
		}
		stmt->fetch.cls.fci.params = NULL;
	}

	stmt->fetch.cls.fci.size = 0;
	if (!Z_ISUNDEF(stmt->fetch.cls.ctor_args) && free_ctor_agrs) {
		zval_ptr_dtor(&stmt->fetch.cls.ctor_args);
		ZVAL_UNDEF(&stmt->fetch.cls.ctor_args);
		stmt->fetch.cls.fci.param_count = 0;
	}
	if (stmt->fetch.func.values) {
		efree(stmt->fetch.func.values);
		stmt->fetch.func.values = NULL;
	}
}
/* }}} */

/* perform a fetch.
 * If return_value is not null, store values into it according to HOW. */
static bool do_fetch(pdo_stmt_t *stmt, zval *return_value, enum pdo_fetch_type how, enum pdo_fetch_orientation ori, zend_long offset, zval *return_all) /* {{{ */
{
	int flags, idx, old_arg_count = 0;
	zend_class_entry *ce = NULL, *old_ce = NULL;
	zval grp_val, *pgrp, retval, old_ctor_args = {{0}, {0}, {0}};
	int colno;
	int i = 0;

	if (how == PDO_FETCH_USE_DEFAULT) {
		how = stmt->default_fetch_type;
	}
	flags = how & PDO_FETCH_FLAGS;
	how = how & ~PDO_FETCH_FLAGS;

	if (!do_fetch_common(stmt, ori, offset)) {
		return 0;
	}

	if (how == PDO_FETCH_BOUND) {
		RETVAL_TRUE;
		return 1;
	}

	if ((flags & PDO_FETCH_GROUP) && stmt->fetch.column == -1) {
		colno = 1;
	} else {
		colno = stmt->fetch.column;
	}

	/* If no return value we are done */
	if (!return_value) {
		return true;
	}

	if (how == PDO_FETCH_LAZY) {
		get_lazy_object(stmt, return_value);
		return 1;
	}

	RETVAL_FALSE;

	switch (how) {
		case PDO_FETCH_USE_DEFAULT:
		case PDO_FETCH_ASSOC:
		case PDO_FETCH_BOTH:
		case PDO_FETCH_NUM:
		case PDO_FETCH_NAMED:
			if (!return_all) {
				array_init_size(return_value, stmt->column_count);
			} else {
				array_init(return_value);
			}
			break;

		case PDO_FETCH_KEY_PAIR:
			if (stmt->column_count != 2) {
				/* TODO: Error? */
				pdo_raise_impl_error(stmt->dbh, stmt, "HY000", "PDO::FETCH_KEY_PAIR fetch mode requires the result set to contain exactly 2 columns.");
				return 0;
			}
			if (!return_all) {
				array_init(return_value);
			}
			break;

		case PDO_FETCH_COLUMN:
			if (colno < 0 ) {
				zend_value_error("Column index must be greater than or equal to 0");
				return false;
			}

			if (colno >= stmt->column_count) {
				zend_value_error("Invalid column index");
				return false;
			}

			if (flags == PDO_FETCH_GROUP && stmt->fetch.column == -1) {
				fetch_value(stmt, return_value, 1, NULL);
			} else if (flags == PDO_FETCH_GROUP && colno) {
				fetch_value(stmt, return_value, 0, NULL);
			} else {
				fetch_value(stmt, return_value, colno, NULL);
			}
			if (!return_all) {
				return 1;
			}
			break;

		case PDO_FETCH_OBJ:
			object_init_ex(return_value, ZEND_STANDARD_CLASS_DEF_PTR);
			break;

		case PDO_FETCH_CLASS:
			if (flags & PDO_FETCH_CLASSTYPE) {
				zval val;
				zend_class_entry *cep;

				old_ce = stmt->fetch.cls.ce;
				ZVAL_COPY_VALUE(&old_ctor_args, &stmt->fetch.cls.ctor_args);
				old_arg_count = stmt->fetch.cls.fci.param_count;
				do_fetch_opt_finish(stmt, 0);

				fetch_value(stmt, &val, i++, NULL);
				if (Z_TYPE(val) != IS_NULL) {
					if (!try_convert_to_string(&val)) {
						return 0;
					}
					if ((cep = zend_lookup_class(Z_STR(val))) == NULL) {
						stmt->fetch.cls.ce = ZEND_STANDARD_CLASS_DEF_PTR;
					} else {
						stmt->fetch.cls.ce = cep;
					}
				}

				do_fetch_class_prepare(stmt);
				zval_ptr_dtor_str(&val);
			}
			ce = stmt->fetch.cls.ce;
			/* TODO: Make this an assertion and ensure this is true higher up? */
			if (!ce) {
				/* TODO Error? */
				pdo_raise_impl_error(stmt->dbh, stmt, "HY000", "No fetch class specified");
				return 0;
			}
			if ((flags & PDO_FETCH_SERIALIZE) == 0) {
				if (UNEXPECTED(object_init_ex(return_value, ce) != SUCCESS)) {
					return 0;
				}
				if (!stmt->fetch.cls.fci.size) {
					if (!do_fetch_class_prepare(stmt)) {
						zval_ptr_dtor(return_value);
						return 0;
					}
				}
				if (ce->constructor && (flags & PDO_FETCH_PROPS_LATE)) {
					stmt->fetch.cls.fci.object = Z_OBJ_P(return_value);
					stmt->fetch.cls.fcc.object = Z_OBJ_P(return_value);
					if (zend_call_function(&stmt->fetch.cls.fci, &stmt->fetch.cls.fcc) == FAILURE) {
						/* TODO Error? */
						pdo_raise_impl_error(stmt->dbh, stmt, "HY000", "could not call class constructor");
						return 0;
					} else {
						if (!Z_ISUNDEF(stmt->fetch.cls.retval)) {
							zval_ptr_dtor(&stmt->fetch.cls.retval);
							ZVAL_UNDEF(&stmt->fetch.cls.retval);
						}
					}
				}
			}
			break;

		case PDO_FETCH_INTO:
			/* TODO: Make this an assertion and ensure this is true higher up? */
			if (Z_ISUNDEF(stmt->fetch.into)) {
				/* TODO ArgumentCountError? */
				pdo_raise_impl_error(stmt->dbh, stmt, "HY000", "No fetch-into object specified.");
				return 0;
				break;
			}

			ZVAL_COPY(return_value, &stmt->fetch.into);

			if (Z_OBJ_P(return_value)->ce == ZEND_STANDARD_CLASS_DEF_PTR) {
				how = PDO_FETCH_OBJ;
			}
			break;

		case PDO_FETCH_FUNC:
			/* TODO: Make this an assertion and ensure this is true higher up? */
			if (Z_ISUNDEF(stmt->fetch.func.function)) {
				/* TODO ArgumentCountError? */
				pdo_raise_impl_error(stmt->dbh, stmt, "HY000", "No fetch function specified");
				return 0;
			}
			if (!stmt->fetch.func.fci.size) {
				if (!do_fetch_func_prepare(stmt))
				{
					return 0;
				}
			}
			break;
		EMPTY_SWITCH_DEFAULT_CASE();
	}

	if (return_all && how != PDO_FETCH_KEY_PAIR) {
		if (flags == PDO_FETCH_GROUP && how == PDO_FETCH_COLUMN && stmt->fetch.column > 0) {
			fetch_value(stmt, &grp_val, colno, NULL);
		} else {
			fetch_value(stmt, &grp_val, i, NULL);
		}
		convert_to_string(&grp_val);
		if (how == PDO_FETCH_COLUMN) {
			i = stmt->column_count; /* no more data to fetch */
		} else {
			i++;
		}
	}

	for (idx = 0; i < stmt->column_count; i++, idx++) {
		zval val;
		fetch_value(stmt, &val, i, NULL);

		switch (how) {
			case PDO_FETCH_ASSOC:
				zend_symtable_update(Z_ARRVAL_P(return_value), stmt->columns[i].name, &val);
				break;

			case PDO_FETCH_KEY_PAIR:
				{
					zval tmp;
					fetch_value(stmt, &tmp, ++i, NULL);

					if (Z_TYPE(val) == IS_LONG) {
						zend_hash_index_update((return_all ? Z_ARRVAL_P(return_all) : Z_ARRVAL_P(return_value)), Z_LVAL(val), &tmp);
					} else {
						convert_to_string(&val);
						zend_symtable_update((return_all ? Z_ARRVAL_P(return_all) : Z_ARRVAL_P(return_value)), Z_STR(val), &tmp);
					}
					zval_ptr_dtor(&val);
					return 1;
				}
				break;

			case PDO_FETCH_USE_DEFAULT:
			case PDO_FETCH_BOTH:
				zend_symtable_update(Z_ARRVAL_P(return_value), stmt->columns[i].name, &val);
				if (zend_hash_index_add(Z_ARRVAL_P(return_value), i, &val) != NULL) {
					Z_TRY_ADDREF(val);
				}
				break;

			case PDO_FETCH_NAMED:
				/* already have an item with this name? */
				{
					zval *curr_val;
					if ((curr_val = zend_hash_find(Z_ARRVAL_P(return_value), stmt->columns[i].name))) {
						zval arr;
						if (Z_TYPE_P(curr_val) != IS_ARRAY) {
							/* a little bit of black magic here:
							 * we're creating a new array and swapping it for the
							 * zval that's already stored in the hash under the name
							 * we want.  We then add that zval to the array.
							 * This is effectively the same thing as:
							 * if (!is_array($hash[$name])) {
							 *   $hash[$name] = array($hash[$name]);
							 * }
							 * */
							zval cur;

							array_init(&arr);

							ZVAL_COPY_VALUE(&cur, curr_val);
							ZVAL_COPY_VALUE(curr_val, &arr);

							zend_hash_next_index_insert_new(Z_ARRVAL(arr), &cur);
						} else {
							ZVAL_COPY_VALUE(&arr, curr_val);
						}
						zend_hash_next_index_insert_new(Z_ARRVAL(arr), &val);
					} else {
						zend_hash_update(Z_ARRVAL_P(return_value), stmt->columns[i].name, &val);
					}
				}
				break;

			case PDO_FETCH_NUM:
				zend_hash_next_index_insert_new(Z_ARRVAL_P(return_value), &val);
				break;

			case PDO_FETCH_OBJ:
			case PDO_FETCH_INTO:
				zend_update_property_ex(NULL, Z_OBJ_P(return_value),
					stmt->columns[i].name,
					&val);
				zval_ptr_dtor(&val);
				break;

			case PDO_FETCH_CLASS:
				if ((flags & PDO_FETCH_SERIALIZE) == 0 || idx) {
					zend_update_property_ex(ce, Z_OBJ_P(return_value),
						stmt->columns[i].name,
						&val);
					zval_ptr_dtor(&val);